My answers are: no and probably not.
In short, the Republicans are far worse than the Democrats, because almost without exception, they want to destroy effective government and enrich the wealthy. The Democrats are mixed: many actually care about helping the public, others are corporatists. But even the corporatist Democrats generally aren't as bad as the Republicans.
Forming another party won't make much of a difference, because the sad fact is: progressives are outnumbered, outgunned, and outspent. There's no easy or fast way to reverse this situation. Even if progressives bolted from the Democratic Party to form their own party, they would still be outnumbered, outgunned, and outspent. The Democrats and Republicans would continue to use populist arguments and would co-opt the progressives' message. Moreover, a third party would probably split the vote on the left, allowing the Republicans to take control.
The Evil Republicans
Almost without exception, Republican politicians are bad news. They want government to serve the interests of the wealthy, the military, and the corporations. They want to dismantle the social safety net, weaken regulation, destroy unions, privatize public schools, and destroy public transportation. They're willing to lie, cheat, and steal to achieve their aims. They're willing to exploit racism, bigotry, and fear. They're OK with waging war for resources. They're fine with bankrupting the US Treasury, intentionally mismanaging agencies, and corrupting government contracts. They're brilliant at character assassination and dirty tricks. They deny basic science. The right wing Noise Machine of Fox News and talk radio perpetuate the myths of an alternate reality in which government and liberals are destroying America.
Republicans are bad, bad, bad.
We all knew this already. So nothing new here.
The Mixed Democrats
As for the Democrats, they're a mixed bag. (Again, we knew this already.) Many Democratic politicians want government to work for the people. But, unfortunately, these good Democrats are outnumbered and outgunned. There are quite a few corporate Democrats, including President Obama and the Blue Dogs. So the corporate Democrats and the Republicans are able to defeat most efforts at reform.
But there really are many good and middling Democrats. On July 27, 102 out of 250 House Democrats (40% of the Democrats) voted against funding the war in Afghanistan. President Obama had to rely on Republicans to continue funding his war. More Republicans (160) voted for the funding than Democrats (148).
The recently passed bill to reform Wall Street actually had some teeth, they say. The Volker rule was weakened, but from what I've read, the bill was surprisingly robust, given Congress's recent performance. As expected, Republicans were nearly united in their opposition to even these modest reforms and the Democrats had to go it alone.
Even the "centrist" corporatist Democrats aren't generally as evil as the Republicans. They wouldn't have gotten us involved in the war in Iraq. They wouldn't have stacked the Supreme Court with right-wing ideologues. They wouldn't have cut taxes as much for the rich. The wouldn't have staffed federal agencies with industry hacks. They're not ideologically opposed to government. They don't deny global warming.
Many Democrats are open to a public option, or even single-payer health care. Had the Democrats gotten strong leadership from President Obama and from Congressional leaders, the health care reform bill could have been a lot better than it was.